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多瑙河流域的塞尔维亚发育着典型的风积黄土-古土壤地层,形成年代至少早于80万年.对塞尔维亚L1～S4黄土古土壤序列进行了系统的磁学参数测量分析,表明塞尔维亚黄土古土壤磁化率性质总体上与中国黄土高原是一致的,即磁化率的变化与成壤强度基本上呈正相关关系.无论是黄土层还是古土壤层,对磁化率起主要贡献的是细粒的超顺磁(SP)颗粒和单畴(SD)颗粒,多畴(MD)颗粒所占比例较小.磁化率在黄土层和古土壤层出现的差异,与成壤作用密切相关.随着成壤作用的增强(从黄土发育至古土壤),细粒的亚铁磁性矿物含量随之增加,样品中强磁性的磁性矿物逐渐增多,磁化率增强.高温热磁曲线研究表明,黄土层样品中对磁化率起主要贡献的是磁铁矿和磁赤铁矿,古土壤层样品则主要为磁铁矿,磁赤铁矿只占有较小的比例,特别是S3和S4古土壤样品,甚至在加热和退热过程中表现出有可逆变化的趋势,表明该剖面S3和S4古土壤层发育期间的成土条件,已经使得磁赤铁矿不再稳定,发生溶解改变,可能暗示了当时更加湿润的成土环境已经超过磁赤铁矿的稳定临界条件.
Serbia, the Danube River basin developed typical wind loess - paleosol stratum, formed at least earlier than 800000 years.Serial magnetic parameters of the ancient loess in L1 ~ S4 of Serbia were measured and analyzed, indicating that the Seric loess paleosol The nature of the rate is consistent with that of the Loess Plateau in China, that is, there is a positive correlation between the change of magnetic susceptibility and the degree of soil-forming intensity. Whether it is the loess layer or the paleosol layer, the main contribution to the magnetic susceptibility is the superparamagnetic (SP) particles and single domain (SD) particles and multi-domain (MD) particles accounted for a small proportion.The difference of magnetic susceptibility in the loess and paleosol layers was closely related to the pedogenesis.With the action of pedogenesis (From loess to paleosol), the content of fine-grained ferrimagnetic minerals increases, the magnetic minerals in the samples increase gradually and the magnetic susceptibility increases.The study on the thermomagnetic curve shows that the magnetic susceptibility Magnetite and maghemite have been the main contributors, while magnetite samples have been predominantly magnetite and maghemite has only a small proportion, especially in the S3 and S4 paleosol samples, even after heating and retreat Hot process The trend of reversible change shows that the conditions of soil formation during the development of the paleosol layer S3 and S4 have made the maghemite no longer stable and undergo a dissolution change that may suggest that the wetter, Stable critical conditions of maghemite.